The patch titled
Subject: mm/hmm: fix bad subpage pointer in try_to_unmap_one
has been added to the -mm tree. Its filename is
mm-hmm-fix-bad-subpage-pointer-in-try_to_unmap_one-v3.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-hmm-fix-bad-subpage-pointer-in-try_to_unmap_one-v3.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-hmm-fix-bad-subpage-pointer-in-try_to_unmap_one-v3.patch
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------------------------------------------------------
From: Ralph Campbell <rcampbell@xxxxxxxxxx>
Subject: mm/hmm: fix bad subpage pointer in try_to_unmap_one
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Link: http://lkml.kernel.org/r/20190724232700.23327-4-rcampbell@xxxxxxxxxx
Fixes: a5430dda8a3a1c ("mm/migrate: support un-addressable ZONE_DEVICE page in migration")
Signed-off-by: Ralph Campbell <rcampbell@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/rmap.c | 7 +++++++
1 file changed, 7 insertions(+)
--- a/mm/rmap.c~mm-hmm-fix-bad-subpage-pointer-in-try_to_unmap_one-v3
+++ a/mm/rmap.c
@@ -1475,6 +1475,13 @@ static bool try_to_unmap_one(struct page
/*
* No need to invalidate here it will synchronize on
* against the special swap migration pte.
+ *
+ * The assignment to subpage above was computed from a
+ * swap PTE which results in an invalid pointer.
+ * Since only PAGE_SIZE pages can currently be
+ * migrated, just set it to page. This will need to be
+ * changed when hugepage migrations to device private
+ * memory are supported.
*/
subpage = page;
goto discard;
_
Patches currently in -mm which might be from rcampbell@xxxxxxxxxx are
mm-document-zone-device-struct-page-field-usage.patch
mm-hmm-fix-zone_device-anon-page-mapping-reuse.patch
mm-hmm-fix-bad-subpage-pointer-in-try_to_unmap_one.patch
mm-hmm-fix-bad-subpage-pointer-in-try_to_unmap_one-v3.patch
mm-migrate-initialize-pud_entry-in-migrate_vma.patch
